You can. There are PCH depended and CPU depended lanes. All Haswell CPUs (currently out anyway) have X16 3.0 lanes. Z87 PCH has X8 2.0 lanes (same as Z68/Z77). Then it just depends on how they were distributed. All SLI capable boards do at least X8/X8 at 3.0.

Yeah you'd think with Neweggs budget they could keep their categories and details a little straighter. The way they list specs is not even uniform although I think that plays to their advantage. So you gotta get the info straight from the horses mouth.